In recent years, instant message service (IMS) has been provided to portable terminal devices such as a cellular phone unit and a PDA (Personal Digital Assistant). The use of the IMS enables real-time exchange of short messages between users connected via a network.
As related arts of the present invention, there are techniques disclosed in Patent Literatures 1 and 2, for example. Patent Literature 1 discloses a technique that enables previewing of new events on a small screen device. According to the technique, in a computing device having a plurality of applications, icons for the plurality of applications are displayed on the small screen. Further, according to the technique, the corresponding icon is visually modified upon occurrence of an event of an application, and when the visually-modified application is selected, previewing of messages for the corresponding application, for example, is displayed.
Patent Literature 2 discloses a communication system in which a server and a client terminal communicate data including an instant message, via a portable terminal. The communication system is intended to immediately notify the client terminal in operation of the transmission of data from the server to the portable terminal.